This invention relates to safety harness systems and more particularly to devices for securing a safety rope to a building.
At present there are available safety harnesses and ropes which are intended to be secured to a structure so that if the wearer of the safety harness falls, their fall will be halted by the safety rope. However the integrity of the entire system relies on the rope being secured to an anchor point which can take the loading applied by a falling person. Such a load may be of the order of 22,000 N (equivalent to the weight of about 2.2 tonnes).
Most buildings or buildings under construction do not have any suitable anchor points, which may lead to a false sense of security if a safety harness is worn and attached to an inappropriate anchor point, or workers not wearing safety harnesses.
A further problem is that the building structure and in particular the roof structure is covered once Fe building is complete, and so it is not possible to attach a safety rope to the buildings structure once finished.
In an attempt to overcome some of the disadvantages of the prior art, the invention in one broad form provides an anchor device for a safety rope, the anchor device including:
receiving means for receiving a safety rope; and
securing means for securing the receiving means to a building""s structure.
The receiving means may be a closed ring or a ring with a movable section or an incomplete ring or similar.
Preferably the anchor device includes a deformable portion which deform under a load.
Preferably the receiving means is spaced from the securing means.
Preferably the receiving means is mounted on a rod or tube. The rod or tube preferably plastically deforms when subject to a predetermined load.
Preferably the rod or tube has a tapered section with the smaller cross-section nearer to the receiving means than the larger cross-section.
Preferably the device includes a mounting for attachment to a building and the mounting has more than one location to receive the securing means.
Preferably the device includes a ring mounted on one end of solid rod which increases in diameter away from the ring. The free end of the rod is preferably of constant diameter and is threaded to screw into a suitable threaded hole.
The hole into which the rod screws into may be mounted on a separate mounting which in turn in secured to the building structure or the rod may crew into a threaded hole on the building structure itself. The mounting may be such that the rod passes through the structure and sandwiches the structure between the rod and the mounting.
The device preferably includes an auxiliary locking nut and the rod is threaded so that when fully inserted a portion of the threaded section remains exposed and the locking nut is secured on the rod on this exposed portion to bear tightly against the mounting or structure.
Preferably the locking nut deforms under a predetermined load applied to the receiving means.
Preferably the length of the rod is such that when secured to a roof truss, the rod may extend through any roof cladding so that the receiving means extends above the roof cladding.
The invention also includes within its scope a beam or truss or similar having means for receiving the anchor device.
The means may be one or more apertures or slots through which the securing means passes to engage a fixing means. The fixing means may be a nut or dip which engages the securing means of the anchor device. If a clip is utilised, preferably it engages the beam or truss to be retained thereon in the absence of the anchor device.
Alternatively, the means for receiving may be one or more apertures or recesses in which the securing means engages. In one form, these may be threaded bores into which a threaded portion of the securing means engages with. Alternatively, the aperture may be unthreaded with a retaining mechanism, such as a spring loaded ball or tooth, to engage part of the securing means when inserted into the aperture.
In a preferred form, the beam is provided with a series of threaded apertures into which a threaded rod of the anchor device is screwed.